fans and pumps i - ibse.hkibse.hk/mebs6008/mebs6008_1617_03-pumps.pdf · fans and pumps i ir. dr....
TRANSCRIPT
![Page 1: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/1.jpg)
Fans and Pumps I
Ir. Dr. Sam C. M. HuiVisiting Assistant Professor
Department of Mechanical EngineeringThe University of Hong Kong
E-mail: [email protected]
MEBS6008 Environmental Services IIhttp://me.hku.hk/bse/MEBS6008/
Aug 2016
![Page 2: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/2.jpg)
Contents
• Centrifugal Pumps
• Pump Arrangements
• Matching Pumps to Systems
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Centrifugal Pumps
• Centrifugal pump• Most widely used in HVAC applications, e .g.
• Hot water systems
• Chilled water systems
• Condenser water systems
• Boiler feed and condensate return pumps
• Operation• Electric motor’s output torque => impeller’s rotation
• Coupling to the pump shaft
• Centrifugal force & tip speed force
![Page 4: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/4.jpg)
(Source: Fundamentals of Water System Design)
Chilled water pumping system
![Page 5: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/5.jpg)
(Source: Fundamentals of Water System Design)
Cooling tower pumping system
![Page 6: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/6.jpg)
(Source: Wang, S. K., 2001. Handbook of Air Conditioning and Refrigeration)
A double-suction, horizontal split-case, single-stage centrifugal pump
Pump motor Centrifugal pump body
Pump Shaft
![Page 7: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/7.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
Typical overhung-impeller end-suction pump
![Page 8: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/8.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2012)
Centrifugal pump
* Video: How does a Centrifugal pump work ? (4:37) https://www.youtube.com/watch?v=BaEHVpKc-1Qhttp://www.learnengineering.org/2014/01/centrifugal-hydraulic-pumps.html
![Page 9: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/9.jpg)
(Source: Fundamentals of Water System Design)
Centrifugal pump, impeller and volute
![Page 10: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/10.jpg)
(Source: Fundamentals of Water System Design)
Impeller action on fluid
* Video: Centrifugal Pump Working (5:54) https://www.youtube.com/watch?v=IiE8skW8btEhttp://www.learnengineering.org/2013/03/centrifugal-pump.html
![Page 11: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/11.jpg)
(Source: Fundamentals of Water System Design)
Flow pattern of impeller/volute action
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Centrifugal Pumps
• Types of centrifugal pumps
• Circulator pump
• Closed-couple end suction pump
• Frame-mounted end suction pump
• Base-mounted horizontal split case pump
• Vertical inline pump
• Vertical turbine single or multistage pump
![Page 13: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/13.jpg)
(Source: Fundamentals of Water System Design)
Circulation pump
![Page 14: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/14.jpg)
(Source: Fundamentals of Water System Design)
Close-coupled end suction pump
![Page 15: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/15.jpg)
(Source: Fundamentals of Water System Design)
Frame-mounted end suction pump
![Page 16: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/16.jpg)
(Source: Fundamentals of Water System Design)
Base-mounted horizontal split case pump
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(Source: Fundamentals of Water System Design)
Vertical inline pump
![Page 18: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/18.jpg)
(Source: Fundamentals of Water System Design)
Vertical turbine pump, wet sump arrangement
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(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
Base plate-mounted centrifugal pump installation
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(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
In-line pump installation
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Centrifugal Pumps
• Variable speed pumps
• Less expensive nowadays
• Centrifugal pump characteristics*
• Total pressure-capacity curve
• Flat curve: applied on closed piping systems with modulating valves
• Steep curve: usually for open piping systems (cooling towers), w/ high pressure, constant flow
• Family of pump performance curves* Video: Centrifugal Pumps | Design Aspects (5:32) https://www.youtube.com/watch?v=pWSyrxFJmt4
http://www.learnengineering.org/2013/03/centrifugal-pumps-design-aspects.html
![Page 22: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/22.jpg)
(Source: Fundamentals of Water System Design)
Total pressure-capacity curve
![Page 23: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/23.jpg)
(Source: Fundamentals of Water System Design)
Flat versus steep pump curves
What does this imply?
![Page 24: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/24.jpg)
(Source: Fundamentals of Water System Design)
Characteristic curves for pump models
![Page 25: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/25.jpg)
(Source: Fundamentals of Water System Design)
Selected pump pressure-capacity curve
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Centrifugal Pumps
• System pressure characteristic curve
• Compared w/: fan-duct system characteristics
• System operating point: intersection of fan curve & system curve
• Pump power (W) = flow (L/s) x pressure (kPa)
• Pump input power
• Pump efficiency
• Matching pump to system curve
• Best efficiency point
![Page 27: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/27.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
![Page 28: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/28.jpg)
(Source: Fundamentals of Water System Design)
Increase of pumping power required with pump flow
![Page 29: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/29.jpg)
(Source: Fundamentals of Water System Design)
Pump efficiency
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(Source: Fundamentals of Water System Design)
Pump efficiency curve
![Page 31: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/31.jpg)
Centrifugal Pumps
• Similarity relationships
• Pump affinity laws (c.f. fan laws)
Function Speed change Impeller diameter change
Flow Q2 = Q1 (N2/N1) Q2 = Q1 (D2/D1)
Pressure p2 = p1 (N2/N1)2 p2 = p1 (D2/D1)
2
Power P2 = P1 (N2/N1)3 P2 = P1 (D2/D1)
3
![Page 32: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/32.jpg)
Centrifugal Pumps
• Pump affinity laws (example)
• A pump is rated at 15 L/s at 200 kPa with a 24 rpm electric motor. What is the flow and pressure if used with a 16 rps motor? Assume no system static pressure.
• Solution:
• Flow: Q2 = Q1 (N2/N1) = 15 (16/24) = 10 L/s
• Pressure: p2 = p1 (N2/N1)2 = 200 (16/24)2 = 88.9 kPa
![Page 33: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/33.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
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Centrifugal Pumps
• Radial thrust• Non-uniform pressure around impeller
• Greatest at shutoff
• Decreases from shutoff to design capacity
• Increase with overcapacity
• Net positive suction (NPS)• Cavitation: vapour pockets form in impeller
passages & may cause damages*
• Net positive suction required (NPSR) - pump
* Video: Cavitation Causes and Effects (16:08) https://www.youtube.com/watch?v=oRYYP4F8LTU
•Cavitation Causes and Effects (16:08) https://www.youtube.com/watch?v=oRYYP4F8LTU•Cavitation Causes and Effects (16:08) https://www.youtube.com/watch?v=oRYYP4F8LTU
![Page 35: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/35.jpg)
(Source: Fundamentals of Water System Design)
Pressures on impeller causing radial thrust
![Page 36: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/36.jpg)
(Source: Fundamentals of Water System Design)
Change in radial thrust versus pumping rate
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Centrifugal Pumps
• Net positive suction available (NPSA)
• For the installation
• Total useful energy above the vapour pressure at the pump suction connection
• Affected by the location of expansion tank
• If NPSA < Pump’s NPSR
• Cavitation, noise, inadequate pumping, etc.
• Avoid problem, NPSA > NPSR
![Page 38: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/38.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
![Page 39: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/39.jpg)
(Source: Fundamentals of Water System Design)
Test setup to determine pump’s NPSR
![Page 40: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/40.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
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Pump Arrangements
• Pump design criteria• Design flow & minimum system flow
• Pressure drop required for the most resistant loop
• System pressure at maximum and minimum flows
• Type of control valve—two-way or three-way
• Continuous or variable flow
• Pump environment, number of pumps and standby
• Electric voltage and current
• Electric service and starting limitations
• Motor quality versus service life
• Water treatment, water conditions, and material selection
![Page 42: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/42.jpg)
(Source: Fundamentals of Water System Design)
Pump selection process
![Page 43: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/43.jpg)
Pump Arrangements
• Pump selection process• Determine the load to be pumped
• Determine design Δt & calculate required flow
• Sum up the load flows to determine total flow
• Determine the “critical path” (most resistant)
• Determine mounting method & support
• Select a pump from manufacturer• Flat curve & steep curve, pump operation & motor
• Check overflow capacity when staging multiple pumps
* Critical Pump Selection - Three Major Issues (20:25) https://www.youtube.com/watch?v=qUONRrP-5pc
![Page 44: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/44.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
Pump selection regions
![Page 45: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/45.jpg)
(Source: Grundfos)
Reduction of theoretical Euler head due to losses
![Page 46: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/46.jpg)
(Source: Grundfos)
Increase in power consumption due to losses
![Page 47: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/47.jpg)
(Source: Fundamentals of Water System Design)
Pump performance data
![Page 48: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/48.jpg)
Pump Arrangements
• Pumping arrangements & control scenarios
• Multiple pumps in parallel or series
• Standby pump
• Pumps with two-speed motors
• Primary-secondary pumping
• Variable-speed pumping
• Distributed pumping
![Page 49: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/49.jpg)
(Source: Fundamentals of Water System Design)
Pump curve for parallel operation
![Page 50: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/50.jpg)
(Source: Fundamentals of Water System Design)
Operating conditions for parallel pump installation
![Page 51: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/51.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
![Page 52: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/52.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
![Page 53: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/53.jpg)
(Source: Fundamentals of Water System Design)
Pump curve for series operation
![Page 54: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/54.jpg)
(Source: Fundamentals of Water System Design)
Operating conditions for series pump
![Page 55: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/55.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
![Page 56: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/56.jpg)
Matching Pumps to Systems
• Good piping system design
• Match system characteristics to pump curve
• Trimming pump impellers
• To reduce flow
• To match partload requirments
• Pump control
• Two-speed pumping & motors
• Variable speed pumping
![Page 57: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/57.jpg)
(Source: Fundamentals of Water System Design)
Typical system curve
![Page 58: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/58.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
![Page 59: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/59.jpg)
(Source: Fundamentals of Water System Design)
Shift of system curves
![Page 60: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/60.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
![Page 61: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/61.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
![Page 62: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/62.jpg)
Matching Pumps to Systems
• Modulation of pump-piping systems
• Throttle volume flow by using a valve
• Change flow resistance – new system curve
• Also known as “riding on the curve”
• Turn water pumps on or off in sequence
• Sudden increase/drop in flow rate and head
• Vary the pump speed
• System operating point move along the system curve
• Requires the lowest pump power input
![Page 63: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/63.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
![Page 64: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/64.jpg)
Matching Pumps to Systems
• Plant loop (at constant flow) (production loop)• To protect evaporator from freezing, a fairly
constant-volume water flow is required
• Building loop (at variable flow)• For saving energy at partload
• A differential pressure transmitter is often installed at the farthest end from the pump
• Primary-secondary loop• A short common pipe connects the 2 loops
![Page 65: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/65.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
Primary-secondary loop and pumping
![Page 66: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/66.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
![Page 67: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/67.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
Constant flow chilled water system
![Page 68: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/68.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
Variable flow chilled water system(plant-building loop)
![Page 69: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/69.jpg)
(Source: Wang, S. K., 2001. Handbook of Air Conditioning and Refrigeration)
![Page 70: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/70.jpg)
(Source: Fundamentals of Water System Design)
Primary-secondary variable speed pumping
![Page 71: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/71.jpg)
(Source: Fundamentals of Water System Design)
Distributed variable speed pumping
![Page 72: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/72.jpg)
(Source: ASHRAE HVAC Systems and Equipment Handbook 2004)
Chilled water system using a plant-distribution-building loop
![Page 73: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/73.jpg)
(Source: Wang, S. K., 2001. Handbook of Air Conditioning and Refrigeration)
![Page 74: Fans and Pumps I - ibse.hkibse.hk/MEBS6008/mebs6008_1617_03-pumps.pdf · Fans and Pumps I Ir. Dr. Sam C. M. Hui ... (Source: ASHRAE HVAC Systems and Equipment Handbook 2004) Base](https://reader034.vdocuments.site/reader034/viewer/2022051600/5a9d8f367f8b9a28388ba38e/html5/thumbnails/74.jpg)
Matching Pumps to Systems
• Chiller plant operation/performance management
• Parallel chiller arrangement
• Series chiller arrangement
• Decoupled chiller arrangement
• Chiller plant control
• Tertiary pumping